/// <summary>
/// Gets the component
/// </summary>
/// <param name="componentNumber">The zero-based index of the component. This number is normally between 0 and 3. Use GetNumberOfComponents for bounds-checking.</param>
/// <returns>the JpegComponent</returns>
public JpegComponent GetComponent(int componentNumber)
{
int tagType = JpegDirectory.TAG_JPEG_COMPONENT_DATA_1 + componentNumber;
JpegComponent component = (JpegComponent)GetObject(tagType);
return(component);
}
/// <summary>
/// Gets the Component Data description
/// </summary>
/// <param name="componentNumber">the component number</param>
/// <returns>the Component Data description</returns>
public string GetComponentDataDescription(int componentNumber)
{
JpegComponent component =
((JpegDirectory)base.directory).GetComponent(componentNumber);
if (component == null)
{
throw new MetadataException("No Jpeg component exists with number " + componentNumber);
}
// {0} component: Quantization table {1}, Sampling factors {2} horiz/{3} vert
string[] tab = new string[] { component.GetComponentName(),
component.QuantizationTableNumber.ToString(),
component.HorizontalSamplingFactor.ToString(),
component.VerticalSamplingFactor.ToString() };
return(BUNDLE["COMPONENT_DATA", tab]);
}
/// <summary>
/// Extracts aMetadata
/// </summary>
/// <param name="aMetadata">where to add aMetadata</param>
/// <returns>the aMetadata found</returns>
public override Metadata Extract(Metadata aMetadata)
{
if (base.data == null)
{
return(aMetadata);
}
AbstractDirectory lcDirectory = aMetadata.GetDirectory("com.drew.metadata.jpeg.JpegDirectory");
try
{
// data precision
int dataPrecision =
base.Get16Bits(JpegDirectory.TAG_JPEG_DATA_PRECISION);
lcDirectory.SetObject(
JpegDirectory.TAG_JPEG_DATA_PRECISION,
dataPrecision);
// process height
int height = base.Get32Bits(JpegDirectory.TAG_JPEG_IMAGE_HEIGHT);
lcDirectory.SetObject(JpegDirectory.TAG_JPEG_IMAGE_HEIGHT, height);
// process width
int width = base.Get32Bits(JpegDirectory.TAG_JPEG_IMAGE_WIDTH);
lcDirectory.SetObject(JpegDirectory.TAG_JPEG_IMAGE_WIDTH, width);
// number of components
int numberOfComponents =
base.Get16Bits(JpegDirectory.TAG_JPEG_NUMBER_OF_COMPONENTS);
lcDirectory.SetObject(
JpegDirectory.TAG_JPEG_NUMBER_OF_COMPONENTS,
numberOfComponents);
// for each component, there are three bytes of data:
// 1 - Component ID: 1 = Y, 2 = Cb, 3 = Cr, 4 = I, 5 = Q
// 2 - Sampling factors: bit 0-3 vertical, 4-7 horizontal
// 3 - Quantization table number
int offset = 6;
for (int i = 0; i < numberOfComponents; i++)
{
int componentId = base.Get16Bits(offset++);
int samplingFactorByte = base.Get16Bits(offset++);
int quantizationTableNumber = base.Get16Bits(offset++);
JpegComponent lcJpegComponent =
new JpegComponent(
componentId,
samplingFactorByte,
quantizationTableNumber);
lcDirectory.SetObject(
JpegDirectory.TAG_JPEG_COMPONENT_DATA_1 + i,
lcJpegComponent);
}
}
catch (MetadataException me)
{
lcDirectory.HasError = true;
Trace.TraceError("MetadataException: " + me.Message);
}
return(aMetadata);
}
/// <summary>
/// Extracts aMetadata
/// </summary>
/// <param name="aMetadata">where to add aMetadata</param>
/// <returns>the aMetadata found</returns>
public override Metadata Extract(Metadata aMetadata)
{
if (base.data == null)
{
return aMetadata;
}
AbstractDirectory lcDirectory = aMetadata.GetDirectory("com.drew.metadata.jpeg.JpegDirectory");
try
{
// data precision
int dataPrecision =
base.Get16Bits(JpegDirectory.TAG_JPEG_DATA_PRECISION);
lcDirectory.SetObject(
JpegDirectory.TAG_JPEG_DATA_PRECISION,
dataPrecision);
// process height
int height = base.Get32Bits(JpegDirectory.TAG_JPEG_IMAGE_HEIGHT);
lcDirectory.SetObject(JpegDirectory.TAG_JPEG_IMAGE_HEIGHT, height);
// process width
int width = base.Get32Bits(JpegDirectory.TAG_JPEG_IMAGE_WIDTH);
lcDirectory.SetObject(JpegDirectory.TAG_JPEG_IMAGE_WIDTH, width);
// number of components
int numberOfComponents =
base.Get16Bits(JpegDirectory.TAG_JPEG_NUMBER_OF_COMPONENTS);
lcDirectory.SetObject(
JpegDirectory.TAG_JPEG_NUMBER_OF_COMPONENTS,
numberOfComponents);
// for each component, there are three bytes of data:
// 1 - Component ID: 1 = Y, 2 = Cb, 3 = Cr, 4 = I, 5 = Q
// 2 - Sampling factors: bit 0-3 vertical, 4-7 horizontal
// 3 - Quantization table number
int offset = 6;
for (int i = 0; i < numberOfComponents; i++)
{
int componentId = base.Get16Bits(offset++);
int samplingFactorByte = base.Get16Bits(offset++);
int quantizationTableNumber = base.Get16Bits(offset++);
JpegComponent lcJpegComponent =
new JpegComponent(
componentId,
samplingFactorByte,
quantizationTableNumber);
lcDirectory.SetObject(
JpegDirectory.TAG_JPEG_COMPONENT_DATA_1 + i,
lcJpegComponent);
}
}
catch (MetadataException me)
{
lcDirectory.HasError = true;
Trace.TraceError("MetadataException: " + me.Message);
}
return aMetadata;
}
